archive/zip: use Modified in FileHeader.FileInfo

The Modified field allows representation of extended timestamps, which provide more accuracy than the legacy MS-DOS timestamps.
The FileInfo method provides an implementation of the os.FileInfo interface for files inside archives.

With this change, we make FileInfo use the Modified field, if present, to return more detailed timestamps from its ModTime method.

Fixes #28350

Change-Id: Ia31b5b871a3e61df38a3a1325787ae23ea0b8088
GitHub-Last-Rev: 13e94be3f8ba58717911354146670fc2bc594692
GitHub-Pull-Request: golang/go#28352
Reviewed-on: https://go-review.googlesource.com/c/go/+/144382
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>

diff --git a/src/archive/zip/struct.go b/src/archive/zip/struct.go
index bd637d185b743c2f75a2e561eeb4854ca2d12abb..686e79781acb69bcefd5017829d12fcf8ccd29a9 100644 (file)
--- a/src/archive/zip/struct.go
+++ b/src/archive/zip/struct.go
@@ -154,10 +154,15 @@ func (fi headerFileInfo) Size() int64 {
        }
        return int64(fi.fh.UncompressedSize)
 }
-func (fi headerFileInfo) IsDir() bool        { return fi.Mode().IsDir() }
-func (fi headerFileInfo) ModTime() time.Time { return fi.fh.ModTime() }
-func (fi headerFileInfo) Mode() os.FileMode  { return fi.fh.Mode() }
-func (fi headerFileInfo) Sys() interface{}   { return fi.fh }
+func (fi headerFileInfo) IsDir() bool { return fi.Mode().IsDir() }
+func (fi headerFileInfo) ModTime() time.Time {
+       if fi.fh.Modified.IsZero() {
+               return fi.fh.ModTime()
+       }
+       return fi.fh.Modified.UTC()
+}
+func (fi headerFileInfo) Mode() os.FileMode { return fi.fh.Mode() }
+func (fi headerFileInfo) Sys() interface{}  { return fi.fh }
 
 // FileInfoHeader creates a partially-populated FileHeader from an
 // os.FileInfo.

diff --git a/src/archive/zip/zip_test.go b/src/archive/zip/zip_test.go
index 3d5c759851a3a4fe0bbfe5e67c057215778ae85f..efdb5bd04477ea0d5717a98e1635663616740c73 100644 (file)
--- a/src/archive/zip/zip_test.go
+++ b/src/archive/zip/zip_test.go
@@ -114,6 +114,47 @@ func TestFileHeaderRoundTrip64(t *testing.T) {
        testHeaderRoundTrip(fh, uint32max, fh.UncompressedSize64, t)
 }
 
+func TestFileHeaderRoundTripModified(t *testing.T) {
+       fh := &FileHeader{
+               Name:             "foo.txt",
+               UncompressedSize: 987654321,
+               Modified:         time.Now().Local(),
+               ModifiedTime:     1234,
+               ModifiedDate:     5678,
+       }
+       fi := fh.FileInfo()
+       fh2, err := FileInfoHeader(fi)
+       if err != nil {
+               t.Fatal(err)
+       }
+       if got, want := fh2.Modified, fh.Modified.UTC(); got != want {
+               t.Errorf("Modified: got %s, want %s\n", got, want)
+       }
+       if got, want := fi.ModTime(), fh.Modified.UTC(); got != want {
+               t.Errorf("Modified: got %s, want %s\n", got, want)
+       }
+}
+
+func TestFileHeaderRoundTripWithoutModified(t *testing.T) {
+       fh := &FileHeader{
+               Name:             "foo.txt",
+               UncompressedSize: 987654321,
+               ModifiedTime:     1234,
+               ModifiedDate:     5678,
+       }
+       fi := fh.FileInfo()
+       fh2, err := FileInfoHeader(fi)
+       if err != nil {
+               t.Fatal(err)
+       }
+       if got, want := fh2.ModTime(), fh.ModTime(); got != want {
+               t.Errorf("Modified: got %s, want %s\n", got, want)
+       }
+       if got, want := fi.ModTime(), fh.ModTime(); got != want {
+               t.Errorf("Modified: got %s, want %s\n", got, want)
+       }
+}
+
 type repeatedByte struct {
        off int64
        b   byte